One for the techies ...

longjaw

At the end of my rock bands rehearsal last night the other guitarist noticed he had played his amp head for two hours with the 16 ohm speaker out connected to an 8 ohm cab.

Now he's worried he could have caused damage to the transformer or the speaker - anyone able to advise?

Cheers

DartmoorHedgehog

Pretty unlikely I'd say (as in it's almost certainly fine), specially if it wasn't played flat out.  But somebody more qualified to answer will hopefully be along soon...

martinw

What he said. Highly unlikely to cause damage, and as it's still working, it hasn't.

ecc83

Yeah, no worries...Worst he has done is take maybe two hours of life off his valves but since that is a wet finger in air number these days, he never gonna tell.

Dave.

ICBM

Definitely no damage, just slightly increased valve wear as Dave said. The power output is actually lower with a mismatch (the opposite of what you get with a downward mismatch on a solid-state amp) so the speakers are actually under less stress, not more, and the transformer probably about the same.

The other way round is actually more dangerous to a valve amp, although even then almost always safe.

longjaw

Thanks for that lads - big sigh of relief from him when I told him!